3,001 research outputs found
Sexual dimorphisms in the dermal denticles of thelesser-spotted catshark, Scyliorhinus canicula (Linnaeus, 1758)
The dermal layers of several elasmobranch species have been shown to be sexually dimorphic. Generally, when this occurs the females have thicker dermal layers compared to those of males. This sexual dimorphism has been suggested to occur as a response to male biting during mating. Although male biting as a copulatory behaviour in Scyliorhinus canicula has been widely speculated to occur, only relatively recently has this behaviour been observed. Male S. canicula use their mouths to bite the female's pectoral and caudal fins as part of their pre-copulatory behaviour and to grasp females during copulation. Previous work has shown that female S. canicula have a thicker epidermis compared to that of males. The structure of the dermal denticles in females may also differ from that of males in order to protect against male biting or to provide a greater degree of friction in order to allow the male more purchase. This study reveals that the length, width and density of the dermal denticles of mature male and female S. canicula are sexually dimorphic across the integument in areas where males have been observed to bite and wrap themselves around females (pectoral fin, area posterior to the pectoral fin, caudal fin, and pelvic girdle). No significant differences in the dermal denticle dimensions were found in other body areas examined (head, dorsal skin and caudal peduncle). Sexually dimorphic dermal denticles in mature S. canicula could be a response to male biting/wrapping as part of the copulatory process
Quantifying physiological influences on otolith microchemistry
Trace element concentrations in fish earstones (‘otoliths’) are widely used to discriminate spatially discrete populations or individuals of marine fish, based on a commonly held assumption that physiological influences on otolith composition are minor, and thus variations in otolith elemental chemistry primarily reflect changes in ambient water chemistry. We carried out a long-term (1-year) experiment, serially sampling seawater, blood plasma and otoliths of mature and immature European plaice (Pleuronectes platessa L.) to test relationships between otolith chemistry and environmental and physiological variables. Seasonal variations in otolith elemental composition did not track seawater concentrations, but instead reflected physiological controls on metal transport and biokinetics, which are likely moderated by ambient temperature. The influence of physiological factors on otolith composition was particularly evident in Sr/Ca ratios, the most widely used elemental marker in applied otolith microchemistry studies. Reproduction also triggered specific variations in otolith and blood plasma metal chemistry, especially Zn/Ca ratios in female fish, which could potentially serve as retrospective spawning indicators. The influence of physiology on the trace metal composition of otoliths may explain the success of microchemical stock discrimination in relatively homogenous marine environments, but could complicate alternative uses for trace element compositions in biominerals of higher organism
Adaptive sampling method to monitor low-risk pathways with limited surveillance resources
The rise of globalisation has led to a sharp increase in international trade,
with high volumes of containers, goods and items moving across the world.
Unfortunately, these trade pathways also facilitate the movement of unwanted
pests, weeds, diseases, and pathogens. Each item could contain biosecurity risk
material, but it is impractical to inspect every item. Instead, inspection
efforts typically focus on high risk items. However, low risk does not imply no
risk. It is crucial to monitor the low risk pathways to ensure that they are
and remain low risk. To do so, many approaches would seek to estimate the risk
to some precision, but the lower the risk, the more samples needed to estimate
the risk. On a low-risk pathway that can be afforded more limited inspection
resources, it makes more sense to assign fewer samples to the lower risk
activities. We approach the problem by introducing two thresholds. Our method
focuses on letting us know whether the risk is below certain thresholds, rather
than estimating the risk precisely. This method also allows us to detect a
significant change in risk. Our approach typically requires less sampling than
previous methods, while still providing evidence to regulators to help them
efficiently and effectively allocate inspection effort.Comment: 12 + 2 pages, 8 figures, 2 table
Preliminary interpretations of seafloor geomorphology from a near-shore multibeam sonar survey; Casey Station, East Antarctica
第6回極域科学シンポジウム[OG] 地圏11月16日(月) 国立極地研究所3階セミナー
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Using an art-based approach to develop critical reflection in initial teaching trainees
This paper outlines a small-scale Case Study, which took place in England, involving six School Direct Primary teacher trainees acting as participants. Important assessment points, evidencing progress against the Teachers' Standards, are 'Units of Learning'. These contain sequences of lessons, planned and evaluated by the trainees, assessing impact on both pupils' progress and their own professional development. The final element of each Unit is a critical reflection and it was felt this needed support. At the start of the project, the reflective elements of the Units of Learning were analysed and, using an online forum, participants shared their understanding of the term 'critical reflection'. Responding to this, a teaching session, using both flipped learning techniques (Flipped Learning Network: 2014) and Loads' 'Cut up and Collage' (2010) approach was designed to support their developing understanding: an approach that could also be applied in different context. It was hoped improved reflection about practice would lead to change and identifiable progress from 'novice' to 'competence'. Subsequent Units of Learning were analysed following the intervention and participants' opinions canvassed to assess how their reflections had developed. Findings revealed some improvement in critical thinking, with participants becoming more reflective about their personal and professional identities as teachers
Implementing a perioperative care of older people undergoing surgery (POPS) service:findings from a multi-site qualitative implementation study
Oystershell Scale: An Invasive Threat to Aspen Conservation
Aspen decline is an acute and chronic problem in Arizona, where high levels of overstory mortality and a lack of recruitment continue to be observed. Oystershell scale (Lepidosaphes ulmi; OSS), an invasive sapsucking insect, has recently become widespread in native aspen stands in the southwestern U.S., further contributing to aspen mortality. Damage is severe in lower elevation stands and within ungulate exclosures created to conserve aspen. Young recruiting aspen that are rare on the landscape incur high levels of OSS-caused mortality when infested (Fig. 1). OSS has only recently become a pest of concern in the Southwest and Intermountain West, and thus, mitigation strategies are lacking for OSS in natural forest settings. OSS is also polyphagous and affects several woody hosts with thin bark, adding to management complexity. Collaborative efforts have been initiated to address OSS biology, natural predators, and management strategies
Realising governmentality: pastoral power, governmental discourse and the (re)constitution of subjectivities
Michel Foucault’s concept of governmentality has been hugely influential in sociology and other disciplinary fields. However, its application has been criticised by those who suggest it neglects agency, and gives overwhelming power to governmental discourses in constituting subjectivities, determining behaviour, and reproducing social reality. Drawing on posthumously translated lecture transcripts, we suggest that Foucault’s nascent concept of pastoral power offers a route to a better conceptualisation of the relationship between discourse, subjectivity and agency, and a means of understanding the (contested, non-determinate, social) process through which governmental discourses are shaped, disseminated, and translated into action. We offer empirical examples from our work in healthcare of how this process takes place, present a model of the key mechanisms through which contemporary pastoral power operates, and suggest future research avenues for refining, developing or contesting this model
DePaul University Centennial Essays and Images
A collection of eight essays honoring DePaul University’s centennial. The book has three parts: Mission and Governance; Campus Culture and Student Life; and Making the Modern University.https://via.library.depaul.edu/vincentian_ebooks/1020/thumbnail.jp
What can Safety Cases offer for patient safety? A multisite case study
Background The Safety Case is a regulatory technique that requires organisations to demonstrate to regulators that they have systematically identified hazards in their systems and reduced risks to being as low as reasonably practicable. It is used in several high-risk sectors, but only in a very limited way in healthcare. We examined the first documented attempt to apply the Safety Case methodology to clinical pathways. Methods Data are drawn from a mixed-methods evaluation of the Safer Clinical Systems programme. The development of a Safety Case for a defined clinical pathway was a centrepiece of the programme. We base our analysis on 143 interviews covering all aspects of the programme and on analysis of 13 Safety Cases produced by clinical teams. Results The principles behind a proactive, systematic approach to identifying and controlling risk that could be curated in a single document were broadly welcomed by participants, but was not straightforward to deliver. Compiling Safety Cases helped teams to identify safety hazards in clinical pathways, some of which had been previously occluded. However, the work of compiling Safety Cases was demanding of scarce skill and resource. Not all problems identified through proactive methods were tractable to the efforts of front-line staff. Some persistent hazards, originating from institutional and organisational vulnerabilities, appeared also to be out of the scope of control of even the board level of organisations. A particular dilemma for organisational senior leadership was whether to prioritise fixing the risks proactively identified in Safety Cases over other pressing issues, including those that had already resulted in harm. Conclusions The Safety Case approach was recognised by those involved in the Safer Clinical Systems programme as having potential value. However, it is also fraught with challenge, highlighting the limitations of efforts to transfer safety management practices to healthcare from other sectors
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